In mining operations, raw ore contains metals of value that are recoverable. Several known techniques, including solvent extraction (“SX”) are used to chemically separate metals from raw ore. In SX, metal ions, for example, copper ions, are leached or otherwise extracted from raw copper ore using chemical agents, such as strong acid. The copper is then plated out of solution onto stainless steel sheets using electrowinning (“EW”) processes. Cobalt, a naturally occurring valuable metal, is added to many copper EW tankhouses to reduce not only corrosion of insoluble lead anodes but also the overvoltage of the oxygen evolution from the anodes. The byproduct of SX is raffinate in which certain metals, including cobalt, may remain after the metal of primary interest, e.g., copper, is extracted from the pregnant leach solution (“PLS”).